Segment and Related Information, Segment Information (Details) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 02, 2022 USD ($)	Oct. 03, 2021 USD ($)	Oct. 02, 2022 USD ($) Segment	Oct. 03, 2021 USD ($)
Segment and Related Information [Abstract]
Number of reportable segments | Segment			3
Net sales	$ 541.9	$ 473.2	$ 1,617.9	$ 1,381.4
Income (loss) from operations	35.6	60.6	171.2	183.1
Performance Materials [Member]
Segment and Related Information [Abstract]
Net sales	290.4	250.4	862.1	719.7
Specialty Minerals [Member]
Segment and Related Information [Abstract]
Net sales	166.0	146.9	493.3	437.4
Refractories [Member]
Segment and Related Information [Abstract]
Net sales	85.5	75.9	262.5	224.3
Reportable Segments [Member]
Segment and Related Information [Abstract]
Net sales	541.9	473.2	1,617.9	1,381.4
Income (loss) from operations	36.1	62.5	178.0	191.8
Reportable Segments [Member] | Performance Materials [Member]
Segment and Related Information [Abstract]
Net sales	290.4	250.4	862.1	719.7
Income (loss) from operations	37.9	32.0	108.5	96.5
Reportable Segments [Member] | Specialty Minerals [Member]
Segment and Related Information [Abstract]
Net sales	166.0	146.9	493.3	437.4
Income (loss) from operations	(14.2)	17.3	24.4	58.4
Reportable Segments [Member] | Refractories [Member]
Segment and Related Information [Abstract]
Net sales	85.5	75.9	262.5	224.3
Income (loss) from operations	$ 12.4	$ 13.2	$ 45.1	$ 36.9